The present invention relates to ground-working tools, such as the type used in power rakes.
Power rakes are conventional ground-working implements which employ a driven drum mounted for rotation about a horizontal axis. The drum carries tools that project outwardly from an outer surface of the drum to cut into the soil to a relatively shallow depth, e.g., no more than a few inches. When provided with tools in the form of tines and applied to established lawns, the power rake performs a dethatching function.
It has also been learned that if tools in the form of rigid bits are mounted on the drum (in lieu of tines), and the power rake is used on compacted bare soil, the bits perform a shallow tilling function to prepare the soil for seeding. Therefore, it has become common to provide a bit-carrying power rake attachment that can be mounted on utility vehicles commonly employed at construction sites, such as front end loaders. Such power rakes can be used following construction of a building to cut open the upper layer of the surrounding soil that has been severely compacted by the passage of utility vehicles so that the soil can be seeded. Such a connection to a front end loader 1 is depicted in FIG. 1. The power rake attachment 2 is connected to the lifting arms 3 of the loader 1 and includes a drum 4 mounted to be driven about a horizontal axis in either direction of rotation, i.e., so the rotation direction of the drum can be changed when the direction of the vehicle is changed. A plurality of radial bits 5 is fixed to the outer surface of the drum to cut the upper soil layer as the drum is rotated while traversing the ground.
The bits 5 are typically welded to the drum surface, which makes it difficult to replace the bits as they become worn. It would, therefore, be desirable to provide a tool, preferably adapted for power rakes, which is relatively easily replaceable.
The present invention relates to a power rake attachment which includes a rotary drum defining a longitudinal center axis, and a plurality of bit assemblies mounted on an outer surface of the drum. Each bit assembly comprises a hollow holder affixed to the outer surface, and a cutter bit including a front cutting head and a rear shank. The shank extends into the holder, and the cutting head projects longitudinally past a front end of the holder. A retainer retains the shank within the holder, and a wear sleeve is disposed around an outer surface of the holder. The cutter bit includes a sleeve-retaining portion projecting laterally outwardly with respect to a longitudinal axis of the bit. The sleeve-retaining portion extends laterally past the outer surface of the holder and into overlying relationship to a front end of the wear sleeve to retain the wear sleeve longitudinally on the holder.